Shape design of magnetic circuit of the magnetic lens based on medial axis transform

He Chen; Quanlin Dong; Xiaomeng Liu; Zhibing Li

doi:10.1016/j.micron.2021.103057

Shape design of magnetic circuit of the magnetic lens based on medial axis transform

Micron. 2021 Jun:145:103057. doi: 10.1016/j.micron.2021.103057. Epub 2021 Mar 19.

Authors

He Chen¹, Quanlin Dong², Xiaomeng Liu¹, Zhibing Li¹

Affiliations

¹ School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing, China; Key Laboratory of Micro-Nano Measurement-Manipulation and Physics, China.
² School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing, China; Key Laboratory of Micro-Nano Measurement-Manipulation and Physics, China. Electronic address: dongquanlin@buaa.edu.cn.

PMID: 33773438
DOI: 10.1016/j.micron.2021.103057

Abstract

This paper proposes a method of designing a magnetic lens circuit based on axial transform theory. A unified mathematical description of the magnetic circuit profile is given within a medial axial transform in differential geometry. The objective constraint and geometric constraint equations of the magnetic circuit form a closed set of differential equations. Lastly, the optimized magnetic circuit is obtained using the solutions of the equations. The optical performance of the magnetic lens is significantly improved.

Keywords: Axial magnetic flux density; Focal length; Magnetic lens; Medial axis transform; Profile equation.